The RUM Construction Kit is a library and editor for creating online Rogue-like, Ultima, or MUD style games.

Classic Ultima Online (CUO) is a modern remake of Ultima I-IV using the RUM Construction Kit. The remake attempts to adhere closely to the original experience of each Ultima, with a few tweaks for online play and to modernize the game somewhat. Some example changes are diagonal movement & attacks, dynamic switching between various graphical tilesets, simplistic UI for Player & NPC interactions, top-down dungeons, plus a handful of new mini-quests.

Please visit for project news and more information.

What is this repository for?

  • Quick summary

This is the open source repository for both the RUM Construction Kit and CUO.

  • Version


How do I get set up?

  • Summary of set up

This is a Mercurial project. You can obtain the repository with the following:

hg clone

hg pull

  • Configuration

Once you have obtained the repository, be sure to read the README.txt and LICENSE.txt files found in the docs subfolder.

Who do I talk to?

  • Repo owner or admin

Visit the contact page of